S² Engine

The S² Engine (S²機関, Esu Esu Kikan), or Super Solenoid Engine, was a perpetual motion organ found within Angels that generated virtually unlimited energy. The engine represented one of the most coveted technologies in the Evangelion universe — a power source that could free the Evangelion units from their dependence on external power cables and umbilical connections.

Overview

The S² Engine operated on the Super Solenoid principle, a theoretical physics concept involving the interaction of electromagnetic fields within a solenoid configuration. In practice, the engine produced a continuous stream of energy without any discernible fuel source or degradation, effectively functioning as a perpetual motion machine. Each Angel possessed this organ naturally, granting them near-limitless operational endurance.

The engine’s energy output was staggering. An active S² Engine could power an Evangelion unit indefinitely, eliminating the operational time limits imposed by conventional power supplies. This capability made the S² Engine the single most desirable piece of Angel technology for military application.

The EVA-04 incident

NERV attempted to install an S² Engine recovered from a defeated Angel onto the fourth Evangelion unit, EVA-04, at NERV’s second branch facility. The experiment resulted in a catastrophic failure. The S² Engine went out of control, triggering an explosion that destroyed the facility and caused a disaster comparable to Second Impact.

The EVA-04 incident, along with the disappearance of the unit and its pilot, demonstrated the extreme danger of attempting to harness Angel technology. The failure revealed that the S² Engine could not simply be transplanted into an Evangelion frame — the biological and metaphysical compatibility between the engine and its host was far more complex than NERV’s engineers had anticipated.

Installation on EVA units

Despite the EVA-04 disaster, NERV eventually succeeded in installing S² Engine equivalents into later Evangelion units. EVA-01 gained a form of S² Engine capability after consuming the Fourteenth Angel’s core during the events surrounding Shinji Ikari’s rescue of Rei Ayanami. This transformation allowed EVA-01 to operate independently of external power for extended periods and was a key factor in the unit’s escalating power and unpredictability.

In the Rebuild films, the S² Engine’s role was further expanded, with multiple Evangelion units demonstrating autonomous power capabilities that echoed the Angels’ own self-sufficiency.

Philosophical significance

The S² Engine’s name carried deliberate religious symbolism — “Super Solenoid” evoked both scientific terminology and the word “solenoid,” which in its coiled form suggested the serpent imagery woven throughout the Evangelion mythos. More importantly, the engine represented a form of perfection that humans could observe but never truly possess: the Angels’ self-sufficiency stood in stark contrast to humanity’s dependence on external resources and connections.

The failed and successful attempts to harness the S² Engine illustrated the franchise’s recurring theme of humanity’s ambivalent relationship with the divine — the desire to appropriate godlike power whilst bearing the consequences of overreach.

See also

• Angels – Natural bearers of the S² Engine
• Evangelion units – Target platforms for S² Engine installation
• NERV – Organisation that attempted to harness the technology
• Entry Plug – The pilot interface system
• Evangelion portal
• About Evangelion

External links

• S² Engine on the Evangelion Wiki